For weeks, Libya's revolutionary leadership has spoken almost in awe of the soldiers who defected from Muammar Gaddafi's army and who would lead the rebel assault to bring him down.

And for weeks, the disorganised civilian volunteers who have rapidly advanced and almost as swiftly retreated along a few hundred miles of desert road have awaited the arrival of these professional soldiers to turn around the revolution's fortunes.

Finally, some made an appearance for the first time at the frontline near Brega. They appeared disciplined, well armed and under command – a stark contrast to the free-for-all of the civilian rebel militia. But there were no more than a few dozen of them and the question still remained: where were the thousands of experienced soldiers that the revolutionary leadership had so often invoked to bolster morale? Did they exist?

While the revolutionary governing council has appealed to foreign governments for larger weapons to confront Gaddafi's tanks and artillery, it has become increasingly apparent that the real issue for the rebels is a lack of discipline, experience and tactics. Even where they have had the advantage, they have been outmanoeuvred in large part because there has been no plan for attack or defence. Instead, the young rebels, full of bravado, charge forward only to turn and flee when they come under fire, often conceding ground.

Some of the rebels have been crying out for leadership. The revolutionary government's de facto finance minister, Ali Tarhouni, was confronted by civilian members of the rebel militia demanding to know who was going to take charge of military strategy on the ground after claiming that there are 1,000 trained fighters among the rebels.

On Friday, two of the senior rebel defectors from the Gaddafi regime, Abdel Fattah Younes, the ex-interior minister, and Khalifa Haftar, the former head of Libya's armed forces, made an appearance at the front to be greeted like heroes.

Wearing sunglasses and a red and green scarf around his neck, Younes toured the frontline near the port of Brega, shaking hands with the crowd of volunteers who formed around him firing their weapons in the air.

While their visit boosted morale at a time when the rebels have been in retreat once again, a more important question remains – whether these men, who have avoided the frontlines for their own reasons, can turn the war around. And from this weekend it is not who is fighting that is the question but who will no longer be fighting, with the US announcement that its warplanes will no longer carry out bombing raids. Even before the American decision, the number of air strikes, mandated by the UN security council resolution 1973, had been sharply diminishing.

On Friday, Nato announced that coalition aircraft had flown 74 strike missions the previous day, down almost a quarter from earlier in the week. Of those missions, US aircraft flew only 10. And that number of strikes looks likely to decline as responsibility passes largely to the UK, France and Canada.

Among the aircraft being withdrawn are the A-10 Thunderbolts and AC-130 gunships which have been used with such devastating impact against Libyan armour.

The slowing of the coalition mission has only helped to contribute to a growing sense that the conflict in Libya is stumbling into a new and uncertain phase, marked not by the strengths of the opposing sides but by a realisation of their weaknesses.

On the rebel side, a familiar scenario has been played out repeatedly as their poorly armed and ill-disciplined fighters have advanced chaotically to occupy towns briefly vacated by Gaddafi's troops, only to be driven back through scores of miles of desert at the first salvo of rocket or tank fire despite the bravado of their rhetoric.

On Gaddafi's side, his armour and aircraft harried by coalition jets, the momentum similarly has faded since his forces were driven back from the edges of Benghazi by the entry of international forces into the conflict.

And the coalition, too – so optimistic at first behind the scenes about being able to lever Gaddafi out of power with a limited air campaign – has also run out of steam as the US has quickly moved to limit its involvement in the war, ruling out ground troops, and its participants have come to realise the limitations of the UN resolution that authorised force in the first place.

Instead, what has begun to emerge is what many feared in the first place – a stalemate, defined by two sides playing a kind of lethal tag in the desert over deserted oil towns.

By last week it had led one of America's most senior officers, General Carter Ham, head of US Africa command, to warn publicly for the first time of what Washington, London and Paris regard as the nightmare scenario. "I do see a situation where that could be the case," he said. "I could see accomplishing the military mission which has been assigned to me, and the current leader would remain the current leader."

Ham's prognosis has been underscored by US intelligence analysis, which has come to the same conclusion. Officials who spoke anonymously to the Washington Post have cautioned against the idea that Gaddafi may be toppled quickly, despite the high-profile defection to London last week of his foreign minister and long-time intelligence chief, Moussa Koussa. "Neither side seems capable of moving the ball down the field," a US official told the paper. "It is also true that neither side has endless resources."

If Ham's message was pessimistic, that delivered to the House armed services committee by Ham's boss, defence secretary Robert Gates, was bleak, not least for those in the opposition listening to his message in Benghazi.

Despite reported ambiguity on Barack Obama's part over the issue of arming and training the rebels, Gates made clear that the Pentagon firmly opposed it. Repeating that it was a "certainty" that no US ground troops would be authorised by Obama, he laid into the rebels' capabilities, describing the opposition as a faction-ridden and disparate "misnomer" whose forces lacked "command and control and organisation". If the opposition needed training and weapons, he said, "someone else" would have to provide it, a declaration that would seem to slam the door on the rebels' hopes of being armed by the West.

And it has not only been US officials who have been speaking their mind. Last week a collection of former British defence chiefs – perhaps reflecting the views of serving senior officers – used the stage of the House of Lords to warn of the dangers of "mission creep" and taking sides in a civil war if it were decided to use ground troops to break the impasse.

What is also true, however, is that in being weakened by the conflict both sides may be forced into new positions suggesting that, ultimately, negotiations rather than military force might bring the crisis in Libya to an end.

On Friday, after weeks of refusing to negotiate with the Gaddafi regime, the head of the opposition's National Council based in Benghazi laid out its terms for a ceasefire, demanding that Gaddafi withdraw all his forces from Libyan cities and allow "peaceful protests" – the latter condition they hope would lead to his ousting.

While Gaddafi officials quickly rejected the offer as "a trick", it is clear, too, that members of Gaddafi's own regime – weakened by defections, including that of Koussa, and damage to the country's economy – have also been attempting to find an end to the crisis, no matter how cynically motivated.

Libya's former prime minister, Abdul Ati al-Obeidi, confirming remarks by US secretary of state Hillary Clinton that regime figures were trying to get in contact, said on Friday: "We are trying to talk to the British, the French and the Americans to stop the killing of people. We are trying to find a mutual solution." His comments followed the disclosure that a senior aide to Gaddafi's powerful son, Saif al-Islam, had met British officials midweek on a visit to London.

While David Cameron and some of his allies in the coalition are hoping that Gaddafi may be forced out by more defections from his inner circle following the example of Koussa, as yet – despite rumours – the most important figures, including the powerful military intelligence chief Abdullah al-Senussi, have shown no real signs of budging.

All of which has raised the increasing prospect that any solution for the crisis in Libya – as things stand now – is more likely to be political than military, a view strongly endorsed by Italy's foreign minister, Franco Frattini.

"It is not through actions of war that we can make Gaddafi leave, but rather through strong international pressure to encourage defections by people close to him," Frattini said. Indeed, Italy is understood to be involved in a search for countries that might be prepared to welcome Gaddafi and his family if he agrees to leave.

This all opens a number of possible scenarios. Gates last week provided one – much wished for by the opposition – that a member of Gaddafi's military "takes him out", then cuts a deal with the opposition. But despite persistent rumours of a failed attack last month by a group of soldiers on Gaddafi's Tripoli compound, this seems like wishful thinking.

Another scenario – suggested by some analysts and officials – is that the regime's attempts to reach out and engage in negotiations are a kind of stalling strategy designed ultimately to split the opposition, which the regime has been doing in any case, trying to separate tribal leaders from the rebels through its own process of "national dialogue", although so far without much success.

Least likely is one of a number of scenarios allegedly most favoured by Gaddafi and family, which would see Gaddafi (or one of his sons) overseeing a transitional period of reform. It is precisely this proposal – which the Turkish media was reporting before the onset of the coalition's air strikes – that Ankara was attempting to broker: envisaging that Gaddafi would cede power to one of his sons ahead of elections.

Whatever the outcome, what seems most unlikely is that the rebels' newly visible generals will be leading their troops into Tripoli any time in the near future.